Improved accumulator for refrigerating system



Nov. 19, 1963 A. G- BUTSCH ET AL IMPROVED ACCUMULATOR FOR REFRIGERATING SYSTEM Filed Sept. 14, 1962 INVENTORS V ALFRED G. su'rscH &CL\FF'ORD M. :rsumns me 4 32 4L THEJR ATTORNEY United States Patent "ice 3,111,135 ll fPPillVlEl) AQCUMULATOR FUR G SYSTrEi /l Alfred G. llutseh and Clifford M. Jenkins, Louisville, Ky, assignors to General Electric (Iornpauy, a corporation of New Yuri:

Filed Sept. 14, 1962, Ser. No. 223,693 Claims. (*Cl. l37-l7l1) The present invention relates to refrigerating systems and is more particularly concerned with an improved accumulator for such systems.

Refrigerating systems of the type used in household refrigerators comprise a compressor, a condenser, a capillary tube, an evaporator and a suction line connected in closed series flow circuit. The evaporator receives liquiiied refrigerant from the condenser by way of the capillary tube while the compressor withdraws gaseous refrigerant from the outlet end of the evaporator. To provide a reservoir for any liquid refrigerant leaving the evaporator and to prevent this liquid refrigerant from being drawn through the suction line into the compressor, a refrigerating system of this type normally includes an accumulator connected between the outlet end of the evaporator and the suction line. The accumulator is designed to accommodate variations in the amount of liquid refrigerant flowing from the evaporator and to separate the liquid refrigerant from the gaseous refrigerant before the gaseous refrigerant is allowed to enter the suction lin To this end the accumulator which normally comprises an elongated tubular or cylindrical member is usually mounted at an angle with its evaporator end at a lower level than the outlet or suction line end to insure the escape of col gaseous refrigerant to the compressor.

in many household ref igerator applications, due to design or other features of the refrigerator, it is not possible to mount the accumulator at angle or in an inclined position. T he present invention has as its principal object the provision of an accumulator which provides the desired functions th reof when mounted in a horizontal position.

Another object of the invention is to provide an improved accumulator including a suction conduit for connecting the accumulator to the suction line of a refrigera tor system, the accumulator chamber and suction conduits being so constructed as to assure proper positioning of the intake or inlet end of the suction line within the chamber during assembly.

A further object of the invention is to provide an accumulator includirv a construction providing an effective deflector to prevent liquid refrigerant from entering the outlet connection.

Additional objects and advantages of the invention will become apparent as the following description proceeds and the features of novelty which characterize the invention will be pointed out with particularity in the claims an- 1187;(1 to and forming part of this specification.

In one aspect thereof, the invention comprises an accumulator including a chamber having an elongated cylindrical or tubular center portion, an inlet at one end and an outlet at the other end. The inlet is adapted to direct any liquid refrigerant flowing from the evaporator into the accumulator upwardly along the top of the chamber in such a Way as to cause the liquid to be distributed over the inner surfaces of the chamber and minimize any surging of liquid refrigerant toward the outlet end of the accumulator. The discharge or suction end of the chamber includes an inclined tubular opening for receiving a suction conduit with the axis of the tubular opening sloping downwardly at an angle to the axis of the cylindrical enter portion of the chamber. A suction conduit or connection having a slanting portion extending through the ubular opening into said chamber terminates above the 3-,l l l, l 35 Patented Nov. 19, 1963 liquid level of the refrigerant in the accumulator in an obliquely cut inlet end, the plane of the inlet end being substantially parallel to the principal axis of the chamber. A flat depressed area provided at the top of the chamber is designed to be engaged by the tip or leading portion of the suction conduit upon insertion thereof into the chamber. By this arrangement, the remaining portion of the inlet end of the conduit is maintained in spaced relationship with the top of the cylindrical center portion of the chamber so that only gaseous refrigerant can flow from the accumulator into the conduit. Liquid refrigerant boiling below the suction conduit is deflected away from the outlet opening by the cylindrical shape of the conduit. Also by contact of the leading portion or tip of the suction conduit with the depressed flattened area, any liquid refrigerant flowing along the top of the chamber is prevented from entering the suction conduit. A further advantage of this structure is that the peripheral elliptical shape of the inlet end of the conduit provides curved or rounded surfaces which, upon contact with the flattened area of the chamber during insertion of the conduit, provide a camming action facilitating positioning the inlet end in a horizontal or upwardly facing position within the header.

For a better understanding of the invention references may be had to the accompanying drawing, in which:

FIGURE 1 is a perspective view partly in section of a refrigerator including a refrigerant circuit. embodying the present invention;

FIGURE 2 is a sectional view of the accumulator of the present invention;

FIGURE 3 is a view taken along line 3-3 of FIGURE 2; and

FIGURE 4 is a plan View of the inlet end of the suction conduit forn ing part of the accumulator of the present invention.

With reference to FIGURE 1 of the drawing, the present invention has been shown in one form as applied to a refrigerator including a freezer compartment 1 and a fresh food compartment 2 closed by doors 3 and 4-. An evaporator 5 in the form of tubing secured to the top, rear and bottom walls of the freezer compartment serves to maintain the freezer compartment at freezing temperatures and the fresh food compartment at fresh food storage temperatures. The refrigerating system comprises a compressor 6, a condenser 7, a capillary flow restrictor 8, the evaporator 5, an accumulator 9 and a suction line 1%) connccted in closed series flow relationshio in such a manner that when the compressor operates, it withdraws vaporized refrigerant from the accumulator and discharges compressed refrigerant into the condenser. Refrigerant condensed in the condenser flows through the capillary into the evaporator.

For maximum efficiency, the evaporator tubing has both its inlet end 14 and its outlet end 15 on the top wall in of the compartment 1, that is, at or above the level of the remaining portions of the evaporator so that liquid refuge-rant present in the evaporator after a compressor on cycle will remain in the evaporator and continue to cool the compartment 1 during the subsequent off cycle. With this arrangement of the evaporator tubing, it is desirable that accumulator 9 also be positioned on tl e top wall of the evaporator structure, that is, in the insulated space between the evaporator structure the top surface 17 of the outer shell of the efrigerator cabinet. Space requirements therefore require that this accumulator be positioned in a horizontal position. The accumulator of the present invention is particularly designed to provide efiect-ive separation of liquid and gaseous refrigoant when operating in a horizontal position.

In the embodiment thereof illustrated in FIGURES 2-4, the accumulator 9 comprises an elongated chamber 2% including a cylindrical center portion 21, a tapered receiving end 22, and a tapered discharge end 23. The chamber 2% is of a volume sufficient to accommodate and retain the maximum amount of liquid refrigerant which may flow from the evaporator into the accumulator during any period of operation of the refrigerating system.

The tapered inlet or receiving end 22 of the chamber Ztl has the general shape of an oblique cone with axis of the cone extending or sloping downwardly from the horizontal axis of the cylindrical portion 21. An inlet opening 25 at the apex of the cone is adapted to receive the outlet end 15 of the evaporator coaxially with the cone axis so that refrigerant entering the accumulator from the evaporator will be directed upwardly against the top wall 27 of the chamber 2% in such a way as to cause any liquid refrigerant to disperse and flow downwardly along the inner surfaces of the chamber. The bottom wall 2-5 of the cone-shaped receiving end is horizontal to permit free drainage of liquid refrigerant back into the evaporator whenever the compressor is not oper-ating.

The discharge or outlet end 23 of the chamber includes a tubular opening 29 having an inclined or sloping axis preferably intersecting the axis of the cylindrical portion 21 and passing through to the top wall 27 of the cylindrical portion 21 at a point which is spaced from the line of intersection 31 of the cylindrical portion 21 and the tapered discharge end 23.

A suction conduit 32 includes an exposed end portion 33 outside of the chamber 2% and a slanting portion 34 disposed within the chamber. The slanting portion 34- of conduit 32 is adapted to be slidably received in the tubular portion 29 and to extend through the tubular opening 29 and upwardly at an angle into engagement with a portion of the top wall 27 of the cylindrical portion 21, in which position its inlet end 35 is above the normal level of liquid refrigerant collecting in the accumulator.

The inlet end 35 of the suction conduit 32 is cut obliquely or at a slant so that, as shown in FIGURE 4, it has an elliptical periphery. This cut is at an angle such that when the suction conduit 32 is in position within the chamber, that is with the portion 34 of the conduit sloping upwardly, the plane of the cut, or in other words the plane of the inlet end 35, is substantially horizontal or in other words substantially parallel to the major axis of the center portion 21 of the chamber Zil. The suction conduit 3-2 provides means for connecting the accumulator to the suction line 17 of the refrigerating system. As shown in dotted lines in FIGURE 2, the end of the line 17 is slipped over the end 33 and is brazed to the tubular inlet 29.

In order to position the inlet end 35 of the conduit 32 in an upwardly facing position and in spaced relationship with the top wall of the chamber 2% so as to permit the flow of gaseous refrigerant from the top of chamber 2t? into the suction line 17 while preventing surges of liquid refrigerant from entering the suction line, the top wall 27 of the chamber is provided with a depressed area 38 having a relatively fiat bottom surface which extends generally horizontally and in spaced relationship with the line 31 forming the junction between the cylindrical portion 21 of the chamber and the tapered outlet end 23. This depression 38 is arranged to be engaged by and seal only the lead portion or tip 42 of the elliptical inlet end 35, that is, the portion of the inlet closest to the inlet end of the chamber, which portion is exposed to the direct flow of any liquid refrigerant entering the chamber through inlet opening 25.

In addition, the depression 3% also serves to maintain the remaining portion of the inlet 35, which is protected from the direct flow of liquid refrigerant by the seal including the lead portion 42, in spaced relationship with the adjacent cylindrical top portion 27 so that gaseous 4 refrigerant can flow between this spaced portion and the top of the chamber into the suction conduit 32.

To facilitate the assembly of the suction conduit 32 in proper position within the chamber Ztl, it is desirable to preform the conduit 32 so that the slanting end portion 24- is bent slightly with reference to the remaining portion 33 of the conduit which will extend outside the chamber. By a bend which places the exposed end 33 substantially horizontal when the inlet end 35 properly engages the depression 38, assembly of conduit 32 is facilitated. The conduit 32 is first inserted part way into the chamber through the tubular opening 29 and twisted until the exposed end of the conduit 32 is in subalignment with the axis of the chamber 26 thus bringing the inlet end 35 to a position substantially pal llel to the depression 38. At this point further insertion of the sloping portion 34 of the conduit into the chamber brings the inlet end thereof into contact with the flattened area or depressed area 38 or an adjacent portion of the top wall 27. if the end 35 of the conduit is in complete alignment or in other words is horizontal when this contact is made, it makes sealing contact with the depressed area 38. if it is not, the initial contact will involve some point on the peripheral edge 39 to one side or the other of the tip 42. Contact of this curved periphery with the chamber surface causes the conduit 32 to rotate by a cam action to the desired position in which the inlet opening is horizontal and in maximum engagement with the depressed area 35.

During operation of the refrigerating system including the accumulator of the present invention, a surge of liquid refrigerant entering the inlet 25' is directed upwardly against the top wall 27 of the cylindrical portion 21 where it spreads over the inner surfaces of the chamber and flows downwardly to the bottom of the chamber where it remains until evaporated or returned to the evaporator. As the contact of the extreme end or tip 42 of the outlet conduit 32 with the flattened portion 38 of the top Wall seals that portion of the conduit 32 directly exposed to such a surge of liquid refrigerant against passage thereof into the conduit 32, any surge of liquid refregerant contacttng the sealed area between the conduit 32 and the top wall 27 will flow downwardly and around the adjacent portions of the chamber 20. Gaseous refrigerant on the other hand flows outwardly through the spaces between the top wall of the chamber and the opposite side edges of the end 35 of conduit 32.

Whenever the refrigerating system is idle it is desirable that any liquid refrigerant remaining in the accumulator be allowed to flow back into the evaporator 4 in order to increase the efiiciency of the refrigerating system since it is the evaporation of liquid refrigerant in the evaporator rather than the accumulator that serves to cool the contents of the refrigerator cabinet. For that reason, the tapered inlet end of the accumulator is designed so that the bottom wall 26 thereof is substantially flat and in the same plane as the bottom wall of the cylindrical portion 21. Liquid regrigerant accumulating in the accumulator can thereby readily flow back into the evaporator 4 whenever the oorpressor is not operating.

While the present invention has been described by reference to a particular embodiment thereof, it is to be understood that modifications may be made by those skilled in the art without actually departing from the invention. Therefore it is intended by the appended claims to cover all such variations as come within the true spirit and scope of the invention.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. An accumulator for a refrigerating system designed to receive a mixture of gaseous and liquid refrigerant and to discharge gaseous refrigerant,

said accumulator comprising a horizontal generally cylindrical chamber including an inlet at one end,

an outlet conduit having a portion extending into the other end of said chamber and terminating in an said accumulator comprising a chamber including a obliquely cut inlet end having an elliptical peripheral horizontal cylindrical center portion and tapered reedge, ceiving and discharge ends, said cylindrical chamber including a substantially horisaid tapered receiving end having the general shape of zontal flattened area in the top thereof in sealing enan oblique cone with a substantially horizontal botgagement only with the leading portion of said periphtom and the axis of said cone sloping downwardly eral edge to prevent surges of refrigerant entering said from the axis of said cylindrical center portion, said chamber from flowing into said conduit. receiving end including an inlet opening coaxial with 2. An accumulator for a refrigerating system designed said cone axis for directing liquid refrigerant entering to receive a mixture of liquid and gaseous vapor refrig- 1 said chamber upwardly against the top of said center erant from an evaporator and to discharge gaseous reportion, frigerant to the suction side of a compressor component said discharge end of said chamber including a tubular of the system, opening for receiving a suction conduit with the axis said accumulator comprising a chamber including a of said tubular opening sloping dot'mwardly at an horizontal cylindrical center portion and receiving angle from the axis of said cylindrical portion, and discharge ends, a suction conduit having a slanting portion extending said discharge end of said chamber including a tubular through said tubular opening into said chamber and opening for receiving a suction conduit with the axis terminating in an obliquely cut inlet end having an of said tubular opening sloping downwardly at an elliptical peripheral edge with the plane thereof subangle from .the axis of said cylindrical portion, stantially parallel to the axis of said center portion, a suction conduit having a slanting portion extending said cylindrical center portion including a flat substanthrough said tubular opening into said chamber and tially horizontal depressed area in the top thereof terminating in an obliquely cut inlet end having an defining a shoulder adjacent to and facing the diselliptical peripheral edge with the plane thereof subcharge end of said chamber, stantially parallel to the axis of said center portion, said depressed area being in sealing engagement with said cylindrical center portion including a fiat substanonly the leading portion of said peripheral edge of tially horizontal depressed area in the top thereof in said suction conduit, sealing engagement with only the leading end portion to thereby maintain the remaining portion of said inlet of said peripheral edge of said suction conduit to end in spaced relation with the top of said cylindrical thereby maintain the remaining portion of said inlet center portion for the flow of gaseous refrigerant end in spaced relation with the top of said cylindrical from said chamber into said suction conduit. center portion for the flow of gaseous refrigerant from said chamber into said suction conduit. Refemllces Ciied in the file Of this Patent 3. An accumulator for a refrigerating system designed UNITED STATES PATENTS to receive a mixture of liquid and gaseous vapor refrigerant from an evaporator and to discharge gaseous re- 2467078 Cahenzlh 1949 2 637 983 Malkoff May 12 1953 frigerant to the suction side of a compressor component of the System 2,783,621 Staebler Mar. 5, 1957 

1. AN ACCUMULATOR FOR A REFRIGERATING SYSTEM DESIGNED TO RECEIVE A MIXTURE OF GASEOUS AND LIQUID REFRIGERANT AND TO DISCHARGE GASEOUS REFRIGERANT, SAID ACCUMULATOR COMPRISING A HORIZONTAL GENERALLY CYLINDRICAL CHAMBER INCLUDING AN INLET AT ONE END, AN OUTLET CONDUIT HAVING A PORTION EXTENDING INTO THE OTHER END OF SAID CHAMBER AND TERMINATING IN AN OBLIQUELY CUT INLET END HAVING AN ELLIPTICAL PERIPHERAL EDGE, 